Here’s my “any input”… I would not suggest widening the front or adding caster as it would increase the jacking and keep the inside rear from helping with your drive off sooner.
Do others run the Mojo Reds? I’ve never run them myself but it might be worth trying higher pressures (say 14 and/or 16 psi hot). If 12 psi hot is the absolutely place to be with tire pressures (or it doesn’t get better with higher pressures) than I would suggest narrowing the rear and going to a medium or long hub. If this doesn’t help than you might want to try without the front bar in.
Do you have any seat struts mounted?